When paired with a 120 mm fan, not all of the Archon's cooling fin surface receives airflow, making it fairly ineffective for an US$80 heatsink. Compared to other performance CPU coolers using the same fan, the Archon's performance was middling.

CPU Coolers (ref. 140mm fan): °C Rise Comparison

Heatsink

Fan voltage / SPL @1m*

9V

7V

6V

18~21 dBA

13~16 dBA

11~13 dBA

Thermalright Archon SB-E

37

40

42

Prolimatech Armageddon

39

42

45

Thermalright Venomous X Silent Edition

40

43

44

NZXT Havik 140

40

43

47

Noctua NH-C14 (top mounted)

40

44

48

Noctua NH-C14

40

44

49

Thermalright Silver Arrow

39

45

49

*Note: there are minor differences in measured SPL due to the variety of fan orientations and mounting methods offered by the compared coolers.

The Archon is a completely different cooler when using a bigger 140 mm fan, topping our chart with a clear margin of victory over the Prolimatech Armageddon, another lanky tower deisnged for a large fan. Heavyweights like the NZXT Havik 140 and Noctua NH-C14 don't match up either, but to be fair, they are optimized for dual fan operation.

FINAL THOUGHTS

Though not marketed as such, the Thermalright Archon SB-E is an exceptional CPU heatsink for low noise operation. Most top tier heatsinks have bulky fin stacks with tight spacing, making it difficult for fans running at low speed to expel the heat. A high pressure fan is best for such heatsink. The Archon employs a somewhat different strategy to great success. Its surface area is very large, and the tall, wide dimensions allows the output of a large fan to reach all of the fins surface area even at very low speed. The distance from the "intake" side of the fin stack to the "exhaust" side is just 53 mm at its maximum, about 20% less than the highest performance 120mm fan heatsinks, which lowers airflow impedance. When tested with our reference Noctua 140 mm fan, the Archon SB-E beat out all comers. The larger stock 150 mm fan had similar effectiveness.

Still, our main caution is about size. At 172 mm, it's one of the tallest heatsinks on the market, too tall for even for fairly big ATX cases. By our measurements, its height exceeds the clearance limit of popular noise-conscious cases like the Corsair Obsidian 550D, Fractal Define Mini, SilverStone Temjin TJ08-E, and Cooler Master Silencio 450/550. Its US$80 street price is hefty, though it isn't unreasonable given its superb performance. Still, there are countless heatsinks that offer good cooling proficiency for much lower cost; the law of diminishing returns is evident in this case. We also are slightly peeved with the tweaked mounting system  specifically the removal of the thumbscrews which made assembling the mounting bracket on the Silver Arrow incredibly easy. There was no reason to meddle with a system that was almost perfect.